org.b3log.latke.util

Class CollectionUtils

java.lang.Object

org.b3log.latke.util.CollectionUtils

public final class CollectionUtils
extends Object

Collection utilities.

Version:

1.0.0.8, Oct 21, 2012

Author:

Liang Ding

Method Summary

Modifier and Type	Method and Description
static <T> Set<T>	arrayToSet(T[] array) Converts the specified array to a set.
static List<Integer>	genIntegers(int start, int end) Generates a list of integers from the specified start(inclusion) to the specified end(inclusion).
static List<Integer>	getRandomIntegers(int start, int end, int size) Gets a list of integers(size specified by the given size) between the specified start(inclusion) and end(inclusion) randomly.
static <T> T[]	jsonArrayToArray(JSONArray jsonArray, Class<? extends T[]> newType) Converts the specified JSON array to an array.
static <T> List<T>	jsonArrayToList(JSONArray jsonArray) Converts the specified JSON array to a list.
static <T> Set<T>	jsonArrayToSet(JSONArray jsonArray) Converts the specified JSON array to a list.
static <T> JSONArray	listToJSONArray(List<T> list) Converts the specified list to a JSON array.
static <T> JSONArray	toJSONArray(Collection<T> collection) Converts the specified collection to a JSON array.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getRandomIntegers

public static List<Integer> getRandomIntegers(int start,
                                              int end,
                                              int size)

Gets a list of integers(size specified by the given size) between the specified start(inclusion) and end(inclusion) randomly.

Parameters:

start - the specified start

end - the specified end

size - the given size

Returns:

a list of integers

genIntegers

public static List<Integer> genIntegers(int start,
                                        int end)

Generates a list of integers from the specified start(inclusion) to the specified end(inclusion).

Parameters:

start - the specified start

end - the specified end

Returns:

a list of integers

arrayToSet

public static <T> Set<T> arrayToSet(T[] array)

Converts the specified array to a set.

Type Parameters:

T - the type of elements maintained by the specified array

Parameters:

array - the specified array

Returns:

a hash set

listToJSONArray

public static <T> JSONArray listToJSONArray(List<T> list)

Converts the specified list to a JSON array.

Type Parameters:

T - the type of elements maintained by the specified list

Parameters:

list - the specified list

Returns:

a JSON array

toJSONArray

public static <T> JSONArray toJSONArray(Collection<T> collection)

Converts the specified collection to a JSON array.

Type Parameters:

T - the type of elements maintained by the specified collection

Parameters:

collection - the specified collection

Returns:

a JSON array

jsonArrayToSet

public static <T> Set<T> jsonArrayToSet(JSONArray jsonArray)

Converts the specified JSON array to a list.

Type Parameters:

T - the type of elements maintained by the specified json array

Parameters:

jsonArray - the specified json array

Returns:

an array list

jsonArrayToList

public static <T> List<T> jsonArrayToList(JSONArray jsonArray)

Converts the specified JSON array to a list.

Type Parameters:

T - the type of elements maintained by the specified json array

Parameters:

jsonArray - the specified json array

Returns:

an array list

jsonArrayToArray

public static <T> T[] jsonArrayToArray(JSONArray jsonArray,
                                       Class<? extends T[]> newType)

Converts the specified JSON array to an array.

Type Parameters:

T - the type of elements maintained by the specified json array

Parameters:

jsonArray - the specified json array

newType - the class of the copy to be returned

Returns:

an array